It is a common practice to perform both diagnostic and therapeutic esophageal endoscopy on human medical patients to discover and rectify abnormalities that may occur in the esophagus and portions of the stomach and duodenum. For example, endoscopy is frequently used in patients suspected of having reflux esophagitis, benign strictures, gastrointestinal distress and bleeding, esophageal rings, esophageal ulcers, malignant tumors and cancers. The aforementioned abnormalities may be treated by various techniques, including laser therapy. This is especially beneficial, among other things, in tumor removal, coagulation of ulcer beds and treatment of certain esophageal cancers. However, along with the many benefits of laser therapy, there are certain disadvantages, including the production of laser smoke which migrates towards the oral cavity, nasal passage and lungs and is injurious to these tissues. Specifically, the smoke causes oxygen depletion in the lungs and may contain viable cancer tissues which can affect the patient and operating room personnel. Another disadvantage of laser therapy is that debris produced from the laser often collects on the distal end of the endoscope. During removal of the endoscope from the patient, this same debris may adhere to any tissue or equipment it contacts, and may adhere to the endoscope during its reinsertion into the patient.
Despite the above-mentioned disadvantages, laser therapy is still widely used in conjunction with a variety of medical devices such as endoscopes, angioscopes, catheters and the like. For example, U.S. Pat. No. 4,770,653 discloses a catheter for laser angioplasty that includes a positioning means in the form of an expandable balloon at its distal end. Expansion of the balloon increases the distal end portion until it contacts the walls of the vascular lumen or other cavity within a patient to form a seal and stabilize the distal end of the catheter. This patent further discloses, and is primarily concerned with, an aiming mechanism for positioning an optical fiber within an arterial lumen so as to direct the fiber towards a particular site therein. Other known devices in this general medical field also include an endobronchial or endotracheal tube having inflatable cuffs which preclude air in the patient's lungs from escaping through the trachea or bronchus.
While the above-cited '653 patent is directed to the aiming or positioning of optical fibers, it does not address the particular problems associated with smoke and debris which are typically encountered in laser surgery. Likewise, the above-mentioned endobronchial and endotracheal tubes address entirely different problems from those which occur in laser surgery.
These aforementioned devices, while providing an effective remedy to various unrelated problems associated with endoscopy, do not teach or suggest any sealing means, or any other means, which solve the specific problem of smoke and debris control encountered in laser surgery.
Accordingly, an object of the present invention is to provide a protective tube for a laser endoscope that prevents the passage of laser smoke towards the oral cavity of a patient and which is adapted to be inserted through the oral cavity and into an esophagus of a patient receiving medical treatment.
Another object of the invention is to provide a protective tube for a laser endoscope that removes debris build-up from the distal end of the endoscope so that this same debris will not adhere to the interior of the protective tube during removal of the endoscope and later cause damage to the endoscope during its reinsertion into the tube.
Another object of the invention is to provide a protective tube for a laser endoscope that is adapted to fit any existing laser endoscope and which may be attached thereto quickly and easily.
Another object of the invention is to provide a protective tube for a laser endoscope that serves as a guide during insertion of the endoscope.
Another object of the invention is to provide a protective tube for a laser endoscope that precludes any tissue injury in the oral cavity and nasal passage.
Another object of the invention is to provide a protective tube for a laser endoscope that may be used for both diagnostic and therapeutic procedures.
Another object of the invention is to provide a protective tube for a laser endoscope that is disposable.
A further object of the invention is to provide a protective tube for a laser endoscope that is easy to manufacture and cost effective to use.